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Message-ID: <a840db62053cf5d3594effd9b1da8761be5676ee.camel@sipsolutions.net>
Subject: Re: [PATCH net] net: core: synchronize link-watch when carrier is
 queried
From: Johannes Berg <johannes@sipsolutions.net>
To: Jakub Kicinski <kuba@kernel.org>
Cc: netdev@vger.kernel.org
Date: Wed, 06 Dec 2023 01:12:26 +0100
In-Reply-To: <20231205161103.3bec2036@kernel.org>
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On Tue, 2023-12-05 at 16:11 -0800, Jakub Kicinski wrote:
> On Mon,  4 Dec 2023 21:47:07 +0100 Johannes Berg wrote:
> > There are multiple ways to query for the carrier state: through
> > rtnetlink, sysfs, and (possibly) ethtool. Synchronize linkwatch
> > work before these operations so that we don't have a situation
> > where userspace queries the carrier state between the driver's
> > carrier off->on transition and linkwatch running and expects it
> > to work, when really (at least) TX cannot work until linkwatch
> > has run.
> >=20
> > I previously posted a longer explanation of how this applies to
> > wireless [1] but with this wireless can simply query the state
> > before sending data, to ensure the kernel is ready for it.
>=20
> Are you okay with net-next?
> The previous behavior is, herm... well established.

Err, yeah, sure! Not sure I can tell you now how I ended up with net
there.

johannes